Note: Descriptions are shown in the official language in which they were submitted.
CA 02361274 2007-11-15
DESCRIPTION
Dynamic seat arrangement
The present invention concerns a dynamic seat arrangement.
The purpose of an arrangement of that kind is to render dynamic the
fact of sitting on a known static seat arrangement such as for example a
chair with a fixed seat surface, and thus to overcome disadvantages
involved in immobile passive sitting in terms of the back musculature and
the intervertebral disks of a user.
More precisely, a known dynamic seat arrangement in which the seat
portion as the actual seat surface is held movably relative to the subjacent
support element means that the user is constantly forced to perform slight
movements in order to achieve an instantaneous equilibrium position, with
the result that the back muscles and the intervertebral disks are kept in
motion, in an orthopedically advantageous manner.
However a dynamic seat aid of the general kind set forth in turn
gives rise to numerous detail problems which in practical use, for example
in the event of major deflections in the tilting movement and/or tilting
options of equal magnitude in the seat direction and in opposite relationship
thereto, are uncomfortable and mean that the user quickly assumes a so-
called comfortable posture which makes it.easier for him to balance but
which at the same time is once again anatomically questionable.
Furthermore the dynamic seat arrangements known from the state of
the art suffer from the disadvantage that they are structurally complicated
and expensive and thus constitute an obstacle to widespread use at low
cost (and thus purchase prices).
Accordingly the object of the present invention is to improve a
dynamic seat arrangement of the general kind set forth, in regard to its
1
CA 02361274 2007-11-15
properties of use, in particular its orthopedic properties, but also in regard
to its suitability for inexpensive, structurally simple manufacture.
In a manner which is advantageous in accordance with the invention
the seat portion and the support element are firstly connected , by a
mounting element which itself is held by an elastic buffer element, in
particular a foam rubber block or the like.
That results in considerable advantages in practice: not only is such
an arrangement inexpensive and simple to produce, but also the buffer
element according to the invention, as the holding means for the mounting
element, permits the structure to be extremely simple, for with suitable
dimensioning of the buffer element in terms of its elasticity, size and spring
force, there is no need for special fastening for the mounting element; on
the contrary the mounting element can be simply embedded at very low
cost, for example in a recess or an incision in the buffer element.
The provision of a buffer element (which is preferably of large
surface area, that is to say which extends over a large part of the seat
surface or the seat portion) of foam material, rubber, horsehair or the like
elastic material permits the use of suitable mounting elements, according
to the needs involved, and more specifically not only at the center of the
buffer element or the seat portion (whereby pivotability about any axes is
guaranteed and axis-specific limitation of the pivotal movement is then to
be effected by way of limiting means which are to be suitably fixedly
mounted or manually fitted), it is also possible to use bar-shaped mounting
elements, a multiplicity of individual mounting elements which are arranged
in adjacent relationship along an axis or the like, in order to determine
center-of-gravity axes of a pivotal movement as between the support
element and the seat portion. In particular however if the elastic buffer
element is of a greater thickness than the height of an inserted mounting
element, for example a bar, such an arrangement, besides a pivotal
movement about the axis defined by means of the bar, permits additional
2
CA 02361274 2001-08-02
slight tilting or pivotal movements along the axis (and thus about a second
perpendicular pivot axis with a reduced pivotal movement) - a structural
advantage which has proven in particular in practice to be an orthopedically
effective improvement in a traditional seat which is pivotable only about
one fixed axis. A further - mechanical - advantage of the provision
according to the invention of a second pivot axis with a different (in this
case: reduced) maximum pivotal movement (that is to say maximum pivot
angle) is the low degree of susceptibility in relation to vibration-induced
fractures or the like material failures in the event of a frequent pulse-like
loading, for example due to heavyweight users.
It is also in accordance with the present invention to adapt the seat
arrangement according to the invention to the needs of the individual user
by suitable means for damping, limiting and/or blocking the pivotal
movement: thus it has also been found to be particularly advantageous if a
user, by manual intervention, can limit a maximum pivotal movement
rearwardly (that is to say in opposite relationship to his seating direction)
while frequently a greater pivotal movement is wanted in a forward
direction (that is to say in the seating direction). That can be achieved by
blocking or limiting means which are arranged fixedly or which if necessary
can be manually inserted and which more preferably can be adjusted. It is
also in accordance with the present invention for a current pivotal position
to be fixed by suitable arresting means, just like, for example by the use of
additional springs or damping elements, individual weights and the
requirement for a softer or a harder elastic behaviour on the part of the
arrangement to be taken into account. A particular area of use of a
damping element of that kind involves damping a pivotal movement in the
forward direction in order to avoid an excessively fast tilting movement of
the pelvis in the seating direction.
A further preferred embodiment of the present invention provides
that the seat portion is designed to be displaceable relative to the support
element, in particular in relation to the seating direction, in which respect
the seat portion can assume relative positions corresponding to
predetermined retaining or detent positions. Those measures make it
3
CA 02361274 2007-11-15
possible to achieve different lever ratios in relation to the seat portion,
linked to suitable orthopedically effective consequences, thus for example
by displacement of the seat portion forwardly in the seating direction (into
a rearward retaining or. detent position of the pivot axis) in order to
increase the tendency on the part of the seat portion to tilt forwardly in the
seating direction. Such a measure promotes tilting of the pelvis of the user
in the forward direction, which results in the entire upper body being
straightened up.
The present invention can be integrated into existing seat
arrangements in many different ways, for example by mounting on or fixing
to static seats; alternatively, it is possible for the seat arrangement
according to the invention itself to be directly provided with legs or a
support structure so that the arrangement itself becomes a chair.
Depending on the respective situation of use, it may also be useful to
provide further damping or elastic means at the floor side (that is to say in
the direction towards a fixed surface or a subjacent carrier means).
According to an aspect of the invention there is provided a dynamic seat
arrangement comprising a seat portion which is movable relative to a support
element by pivoting about a first pivot axis with a first maximum pivotal
movement, wherein provided between the seat portion and the support element
is at least one mounting element to define a mounting between the support
element and the seat portion with the first pivot axis, wherein the at least
one
mounting element is held by an elastic buffer element which at least partially
surrounds the at least one mounting element and which affords a spring force
for
the mounting, wherein the buffer element can be so designed that either a
pivotal
movement about a second pivot axis which is different from the first pivot '
axis
with a second maximum pivotal movement which is different from the first
maximum pivotal movement, or pivotal movement only about the first pivot axis
is
made possible, by the mounting, and wherein there are provided means for
adjustable displacement of the seat portion relative to the support element in
a
displacement plane defined by the seat portion or the support element.
According to another aspect of the invention there is provided a dynamic
seat arrangement comprising a seat portion which is movable relative to a
4
CA 02361274 2007-11-15
support element by pivoting about a first pivot axis, movement provided
between
the seat portion and the support element is an elastic buffer element as a
damping and/or mounting element, and there are provided means adjacent to or
embedded in the buffer element, for displacement of the seat portion relative
to
the support element in a displacement plane defined by the seat portion or the
support element, with at least one fixed relative position between the seat
portion
and the support element.
Further advantages, features and details of the invention will be
apparent from the description hereinafter of preferred embodiments and
with reference to the drawings in which:
Figure 1 is a diagrammatic side view of the dynamic seat
arrangement according to a first embodiment of the present invention,
Figure 2 shows an alternative configuration of the first embodiment
of Figure 1,
Figure 3 is a diagrammatic side view of the dynamic seat
arrangement according to a second embodiment of the present invention,
Figure 4 through Figure 9 show different implementations
(alternative configurations) of the mounting element for use in the dynamic
seat arrangement of the present invention,
Figure 10 through Figure 12 show various displacement positions of
the dynamic seat arrangement of the second embodiment of Figure 3,
Figures 13 and 14 show diagrammatic side views of the dynamic seat
arrangement according to a third embodiment, and
4a
CA 02361274 2001-08-02
Figure 15 through Figure 18 show views from below and
diagrammatic side views respectively of the dynamic seat arrangement
according to the third embodiment.
As shown in Figure 1, the dynamic seat arrangement, in a first
preferred embodiment (best mode) has a base plate 10 comprising a strong
material such as wood, which on its top side is formed with an elastic
cushion layer 12, for example of foam rubber or the like, and covered with
a cover (not shown). A user takes up a position on the cushion layer 12, in
which case the direction of view of the user (hereinafter also referred to as
the seating direction) is Indicated by the arrow 14 in Figure 1 (this equally
also applies however to all further side views).
Fixed beneath the base plate 10 is an elastic buffer block 16 which
comprises foam rubber and which in turn rests by way of an adhesive layer
18 (anti-slip) on a subjacent support plate 20. Alternatively or additionally,
fixing of the buffer block 16 (with the base plate 10 fixed thereto) Is
possible by means of lateral holding bars 22.
Embedded in the buffer block 16, as shown in the diagrammatic view
of Figure 4, is a bar-shaped mounting element 24 of circular or oval cross-
section, in which respect, as can be seen from Figure 1 and Figure 4
respectively, the mounting element 24 of pressure-resistant material (for
example plastic material or wood) is surrounded both in the lateral
direction (that is to say on both sides of end faces of the mounting element
24) and also in relation to a height of the buffer block 16 (vertical
direction
In Figure 1) by the foam material of the buffer block 16. In a structurally
simple fashion, for example the mounting element 24 is inserted into a cut-
out or incision (not shown) in the buffer block 16 and is thereby held in the
position shown in Figure 1 and Figure 4 respectively.
That means that, in relation to the support plate 20 or in relation to
the (suitably fixed) holding bar 22, the base plate 10 is pivotable about the
pivot axis which is determined by the mounting element 24, in accordance
with the elasticity of the buffer block 16 and the maximum pivot angle
determined by the geometry of the arrangement shown in Figure 1 (which
typically is approximately 15 ). However, as shown in Figures 1 through 3,
5
CA 02361274 2001-08-02
in opposite relationship to the seating direction 14, the maximum pivot
angle is additionally limited (or braked) by a diagrammatically illustrated
blocking element 26 which can preferably be set in at least one position
and which is for example in the form of a transverse bar, so that the level
of comfort of use can be enhanced and any risk of accident due to an
excessively large pivot angle in a rearward direction can be alleviated. In
addition, Figures 1 through 3 all show transverse bars (alternatively: foam
elements or the like) as a grip protection 28 in the regions which are at the
front and the rear in relation to the seating direction 14, in order to
prevent
a user inadvertently catching his hands therein or to keep the hands out.
The support plate 20 (which alternatively can also be omitted), the
grip protection elements and/or the holding bar or bars 22 can be fixed by
suitable fixing means (not shown in the Figures), for example apertures for
screws or the like, on a subjacent supporting or carrier unit, in particular
also on a chair surface, so that in that way by virtue of the present
invention conventional non-dynamic seat furniture can be provided with the
advantageous utility of the present dynamic seat arrangement, easily and
at a very low level of equipment expenditure. It is also possible for example
for the - elastic - adhesion or anti-slip layer 18 to be merely put down on to
a subjacent surface, in which case the arrangement can already suitably be
fixed in position by virtue of the adhesion effect thereof.
In addition or alternatively it is possible for the (diagrammatically
illustrated) support plate 20 to be provided at the floor side with suitable
chair legs, feet or the like, so that this can directly provide a dynamic item
of seat furniture (as a single-seater or multi-seater, possibly with
arrangements which are pivotable separately relative to each other, as
shown in Figure 1).
Figures 4 through 9 are a diagrammatic view from below (that is to
say viewing from below on to the base plate 10) of various possible ways of
embodying the mounting element 24: thus it is possible for the axis-shaped
configuration shown in Figure 1 and Figure 4 to be replaced by two or more
mounting elements 30, 32 which are disposed along an axis and which are
in the form of balls, parallelepipeds or blocks, in which respect, in
6
CA 02361274 2001-08-02
accordance with a preferred development of the invention, the provision of
only one central mounting element 30, 32 in the manner shown in Figure 7
or Figure 8 provides that pivotability of the arrangement according to the
invention about only one axis (in particular a transverse axis with respect
to the seating direction, as shown in Figure 1 or Figures 4 through 6
respectively) can be achieved by unlimited pivotability in the manner
defined by the base plate 10 or the support plate 20 respectively, in which
case a main axis of movement in the seating direction 14 is particularly
preferred and differs in terms of its pivotal stroke movement from lateral
pivotal motions. The alternative configuration shown in Figure 2 clearly
illustrates in the side view therein the parallelepipedic shape of a mounting
element 30, as is used for example in the configuration illustrated in Figure
5 or Figure 7 respectively.
Figure 9 shows a particular embodiment of the present Invention:
this arrangement does not have a separate mounting element and the
mounting action in accordance with the invention is ensured by a buffer
block 16 (which in this respect additionally performs the function of the
mounting element). In this case also therefore a pivotal movement Is not
fixed in relation to an axis, but pivotal movement or tilting movement of
the base plate 10 relative to the support plate 20 or relative to the holding
bars 22 takes place in any fashion determined by the buffer block 16 and
the elasticity thereof, with a main axis of movement which is set to the
seating direction 14.
While, as shown in Figure 1 and Figure 2 respectively, a fixedly
mounted blocking element 26 limits a maximum pivotal movement, It Is
possible for that to be implemented in various other ways: thus, instead of
the illustrated element which is parallelepipedic in cross-section, it is
possible to provide balls or the like elements, in particular also mounted
manually in the internal space 34 defined between the base plate 10 and
the support plate 20, displaceably for varying the blocking angle, or It is
possible to provide on the base plate 10 and/or the support plate 20 and/or
a holding bar 22, preferably in the rearward region with respect to the
seating direction 14, a blocking arrangement (not shown) which can be
7
CA 02361274 2001-08-02
turned in, folded in, or pivoted in and which if necessary is introduced by a
user into the space 34 in such a way that the maximum pivotal movement
can be effectively limited thereby. In accordance with a further
embodiment moreover a lifting or blocking arrangement of that kind is
provided with an adjusting mechanism which permits the user to set a
maximum blocking angle in respect of pivotability.
Figure 3 and Figures 10 through 12 are diagrammatic side views
showing a further embodiment of the present invention, illustrating possible
ways for relative displacement between the base plate 10 and holding bars
22 (in addition to or alternatively to a support plate 20 (not shown in the
Figures), similarly to Figure 1). The second embodiment is to be interpreted
in particular also supplemental to the pivotability described hereinbefore
with reference to Figures 1, 2 and 4 through 9.
As shown in Figures 3 and 10 through 12, displacement in the
seating direction (direction of the arrow 14) is achieved by a loop
arrangement 36 (alternatively: belt arrangement or the like) which is of an
inverted U-shape configuration and which is afforded on a lateral pair of
holding bars 22 and which on both sides laterally embraces the buffer block
16 and which extends with its closed central portion between the limbs
above the base plate 10 so that the loop arrangement 36 with the buffer
block 16 carried thereon and the pair of holding bars 22 at both sides can
be displaced between a position of being advanced in the seating direction
(Figure 11) and a rearward position in the seating direction (Figure 12).
The Figures do not show a retaining or fixing unit which is operative
together with the displacement mechanism of Figures 3 and 10 through 12
and which, for example by virtue of fixing of the loop arrangement 36
(alternatively: belt arrangement or the like) to the base plate 10, at
predetermined relative displacement positions, permits latching
engagement or secured fixing of a position of use which is set in the
desired manner by means of displacement of the arrangement.
A detent or fixing device which is particularly suitable in accordance
with the present invention for that purpose is to be found in the third
embodiment shown in Figures 13 through 18: as can be seen in particular
8
CA 02361274 2001-08-02
in the diagrammatic side view in Figures 13, 14 and 18, the buffer block 16
encloses a pair of mounting blocks 38 which are arranged at both sides
laterally and which are respectively adapted to co-operate with a loop 42,
provided with detent or retaining grooves 40, on the base plate 10; as
Figure 13 (front retaining or detent position), Figure 14 (rear retaining or
detent position) and Figure 18 (central retaining or detent position in a
slightly modified embodiment) show, the engagement of a mounting pin 44
of a mounting block 38 into a retaining or detent groove 40 fixes the
relative position of the base plate 10 with the cushion layer 12 resting
thereon, with respect to the subjacent support plate 20, more specifically
just by virtue of the inherent weight of the arrangement 10, 12, with an
increase in the fixing action when a loading is applied by virtue of a user
sitting on the seat arrangement. The mounting pin 44 thus then also
defines the pivot axis.
Figure 17 is a diagrammatic view from below showing the
arrangement of the retaining or detent arrangement embedded in the
buffer block 16 and comprising the mounting blocks 38 and the loops 42,
while Figures 15 and 16 show a slightly modified alternative configuration:
here the buffer block 16' is shortened in relation to the direction defined by
the pivot axis, so that the arrangement comprising the mounting block 38
and the loop 42 is disposed laterally outside the buffer block 16.
The present invention is not limited to the illustrated embodiments;
thus it is in particular in accordance with the present invention for features
of the illustrated embodiments to be combined in any manner and thus to
arrive at forms of implementation of the invention, which depending on the
needs involved afford the appropriate configuration for a respective
purpose in use.
In particular, it is also in accordance with the invention for the buffer
block 16 (which, as an alternative to the described embodiments
comprising foam material, can also be made from other suitable elastic
natural or synthetic materials such as for example latex, horsehair or the
like), to be supplemented or supported in terms of its buffer action by
additional spring or buffer elements (not shown in the Figures); thus, it is
9
CA 02361274 2001-08-02
particularly preferred to associate with the buffer block in a position
adjacent thereto in or in opposite relationship to the seating direction 14,
an additional buffer element in the form of a coil spring, a block of elastic
material or the like, and further preferably to make such an element which
in particular can also be viewed as a damping element adjustable in respect
of its damping action or its buffer action, as can be effected for example in
the case of coil springs by adjustment of the spring travel or the like.
It is also particularly preferred in accordance with the present
invention for the cushion layer 12 (which is suitably covered) to be
supplemented by a further support, illustrated for example as a support
layer 46 in Figure 3, in order in that way to provide for additional
adaptation to a user or the body weight of the user, by virtue of choosing a
suitable material for the support layer, for example strong stable foam
material.
A further preferred development of the invention provides that, in
addition (or alternatively) to limiting a maximum pivotal movement, there
are provided means which can fix an instantaneous pivotal position of the
arrangement, for example by rearwardly or laterally engaging clamp, lever,
blocking or push-in arrangements, so that a user can as desired
(releasably) prevent any dynamic mobility of his seat surface relative to the
subjacent support.
Accordingly therefore the present invention can provide a very high
degree of variability In terms of carrying Into effect the advantages of a
practical, dynamic seat arrangement which is simple to manufacture.